Question

At the link-layer, a crc code is used for error detection, and therefore allows us to identify and correct any corrupted bits without resending the corrupted data.

O true
O false

Answer 1

The statement that at the link-layer, a CRC code is used for error detection, and therefore allows us to identify and correct any corrupted bits without resending the corrupted data, is false.

Step-by-step explanation:

CRC, which stands for Cyclic Redundancy Check, is indeed used for error detection at the link layer. However, CRC is primarily an error-detecting code that detects accidental changes to raw data.

If the CRC values of the sender and receiver do not match, the receiving side can detect that an error occurred, but it does not have the ability to correct the error. The mistake can only be corrected by requesting a retransmission of the entire data.

There are other error-correcting codes like Hamming code and Reed-Solomon that can both detect and correct errors without necessarily resending data, but CRC itself does not have error correction capabilities.

Therefore, the claim that at the link-layer, a CRC code is used for error detection, and therefore allows us to identify and correct any corrupted bits without resending the corrupted data, is false.